Planet Spaceball, led by the incompetent President Skroob, has squandered all of its fresh air. Skroob schemes to force King Roland of the neighboring planet Druidia to give them the code to the shield that protects Druidia, allowing them to steal all their air, by kidnapping his daughter Princess Vespa on the day of her Arranged marriage to the Narcolepsy Prince Diazepam. Skroob sends the villainous Dark Helmet to complete this task with ''Spaceball One'', an impossibly huge ship helmed by Colonel Sandurz. Before they can arrive, Vespa abandons her wedding and flees the planet in her Mercedes-Benz spaceship with her droid of honor, Dot Matrix.